Visual C++ .NET/Class/Constructor

Материал из .Net Framework эксперт
Версия от 12:05, 26 мая 2010; Admin (обсуждение | вклад) (1 версия)
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Adding Constructors

 
#include "stdafx.h"
using namespace System;
ref class ParentClass{
public:
    ParentClass() : PVal(10) {}
    ParentClass(int inVal) : PVal(inVal) {}
    ParentClass(const ParentClass %p) : PVal(p.PVal) {}
    int PVal;
};
ref class ChildClass : public ParentClass{
public:
    ChildClass () : CVal(20) {};    // default constructor
    ChildClass (int inVal1, int inVal2) : ParentClass(inVal1), CVal(inVal2) {}
    ChildClass(const ChildClass %vals) : ParentClass(vals.PVal), CVal(vals.CVal) {}
    int CVal;
};
void main()
{
    ParentClass p1(4);    
    ParentClass p2 = p1;  // Copy Constructor
    p1.PVal = 2;          
    Console::WriteLine("p1.PVal=[{0}] p2.PVal=[{1}]", p1.PVal, p2.PVal);
}


Constructor inheritance

 
#include "stdafx.h"
using namespace System;
ref class MyBase{
    int data;
  public:
    MyBase() { Console::WriteLine("MyBase::MyBase()"); }
    MyBase(int data_in) : data(data_in) { Console::WriteLine("MyBase::MyBase(int)"); }
};
ref class Derived : MyBase
{
   public:
     Derived(int data) : MyBase(data)
     { Console::WriteLine("Derived::Derived(int)"); }
};
int main()
{
    MyBase b;
    Derived d(100);
}


Constructor order

 
#include "stdafx.h"
using namespace System;
class MyClass
{
   public:
   MyClass()
   {
      Console::WriteLine("MyClass: Field constructor.");
   }
};
ref class MyClass2
{
   public:
   MyClass2()
   {
       Console::WriteLine("MyClass2: Field constructor.");
   }
};
class MyBaseClass
{
   public:
     MyBaseClass()
     {
        Console::WriteLine("MyBaseClass: Base class constructor.");
     }
};
class NativeDerived : MyBaseClass
{
   MyClass field;
   public:
     NativeDerived() : field()
     {
         Console::WriteLine("Native: Derived class constructor.");
     }
};
ref class ManagedBase
{
   public:
     ManagedBase()
     {
        Console::WriteLine("ManagedBase: Base class constructor.");
     }
};
ref class ManagedDerived : ManagedBase
{
   MyClass2 field;
   public:
     ManagedDerived() : field()
     {
         Console::WriteLine("ManagedDerived: Derived class constructor.");
     }
};
int main()
{
   NativeDerived nd;
   ManagedDerived md;
}


public constructor

 
#include "stdafx.h"
using namespace System;
ref class MyClass
{
   public:
   literal String^ name = "Bob";
   MyClass()
   {
       Console::WriteLine(name);
   }
   void Print()
   {
       Console::WriteLine(name);
   }
};
int main()
{
   MyClass^ c = gcnew MyClass();
   c->Print();
   Console::WriteLine( MyClass::name );
}